I am his Apprentice, and you are not the first Dark One I have faced.
The Sorcerer's Apprentice is a supporting character on Once Upon a Time. As a boy he became under the employ of the benevolent mage Merlin and, as he grew older, he was only able to scarcely communicate with his trapped master, still carrying out his will as he dedicated a majority of his life to protecting the Sorcerer's hat from various Dark Ones. He often made deals on Merlin's behalf, providing magic to those who needed it, and even after the Dark Curse was cast - despite being stuck in Storybrooke - he found a way to venture out and set certain things straight. Eventually though, he himself was trapped in the hat, and soon after his release he was killed by the very darkness he spent years trying defeat.
Before the Curse
You're an errand boy long past his prime.
The Apprentice learns a valuable lesson from his master. ("Nimue")
Merlin, the most powerful Sorcerer who ever lived due to drinking from the holy grail five-hundred years prior, becomes a healer for a small village in Camelot. A young boy rises as his Apprentice, holding appointments and such for Merlin, who cures the various ailments of the villagers. One day, the Apprentice is standing by as Merlin heals an old woman, then telling him that that was his last appointment of the day. However, there is a woman nearby who the Apprentice didn't see, and the young boy offers to get rid of her. Merlin tells him not to, approaching the woman and growing intrigued by her because he cannot see her future. She reveals that her name is Nimue and she and Merlin soon enter a relationship... but she betrays him by drinking from the holy grail herself and using her new magical abilities to kill, thus turning her into the first Dark One. She snaps the sword forged by Merlin and so the latter and his Apprentice hide it in a stone, then taking the tip and forging it into a dagger which they tether to Nimue's spirit, making it able to control her. The Apprentice says that it's a shame Merlin couldn't see her future because then he could just never have talked to her in the first place, but the Sorcerer tells him not to think like that because life is made up of moments and he had some of the best moments of his life with her. ("Nimue")
The Apprentice defends the hat. ("The Apprentice")
In a dark underground lair lit only by dim fires is a man in a red cloak sweeping the floor. Suddenly, there is a haunting gust of wind that blows out all the torches in the room, the man is alarmed. He drops his broom and pulls out a sword, almost routinely stating "Show yourself Dark One". "You are not the sorcerer" a mystical voice echoes from behind him. The man turns around to see a cloaked figure headed towards him, waving the dagger of the Dark One. "No, I am his apprentice. And you are not the first Dark One I have faced" the man tells his foe. The apprentice charges towards the Dark One and swings his sword, but he vanishes into thin air, reappearing behind him. The apprentice tries again, but this time is sent flying back and to the floor with a push of magic. The Dark One then turns his attention to a box in the middle of the room which rests on a stone table. As the Dark One prepares to open it, the apprentice warns that he doesn't want to know what he'll unleash if he opens the box. The Dark One removes his hood, revealing himself to be Zoso, and he says the sorcerer should not have put his faith in someone like him. He then takes his dagger and waves it across the box, but is instantly blasted with a protective shield, sending him flying through the air. The apprentice gets to his feet and reveals he isn't the only thing his master has faith in, referring to the magical shield. Zoso is furious that there's an enchantment on the box. The apprentice reveals that no one who has ever succumbed to the darkness in their heart can open it. He tells Zoso to be gone, and with that, he vanishes. "Every Dark One has tried, but no Dark One will ever possess what is in that box" the apprentice says to himself, now alone. ("The Apprentice")
The Apprentice tests Isaac. ("Operation Mongoose, Part 1")
In December 1966 in the land without magic, Isaac Heller is hired by a TV salesman named Hank because he hears he's a writer, and therefore assumes he's good at telling stories. However, one day, Isaac fails to sell a television to a couple because he rambles on about what Hank believes is "weird technical crap", leading him to tell his employee that he doesn't tell the kind of stories people want to hear. Isaac, who's just received an offer from a publisher, begs to differ, proceeding to make his way to Star Publishing where the Sorcerer's Apprentice awaits. He tells Isaac to pick a quill out of the five laid out in front of him, and Isaac goes for the fountain pen in the middle, which glows blue when he picks it up. This confuses him greatly, and the Apprentice explains that he is now the new Author, tasked with recording the greatest tales of all time for posterity - sadly, their most recent Author passed away. Isaac is given the opportunity to travel across realms and prove himself and he takes it, excited to prove the people like Hank, who fancy themselves "heroes", wrong. ("Operation Mongoose, Part 1")
Mickey Mouse comes to the rescue. ("The Apprentice")
Anna visits Rumplestiltskin at his Dark Castle and wants to know why her parents came to the Enchanted Forest all those years ago, offering to do whatever it takes for this information. This gladdens Rumple and he makes the princess sign a contract, sending her on her way to poison a sorcerer's apprentice who guards a magic hat. She goes, but cannot poison him, shocked to learn that the "poison" was actually an antidote to the spell Rumple had earlier enacted to turn the kindly old man into a mouse; he explains that he needed her tear to break the enchantment guarding the box containing the hat, which can only be broken by those who've faced their inner-darkness and overcome it. She argues that she never even considered killing the man, so it doesn't count, and so he tells her that her parents came to the Enchanted Forest because they feared their daughter Elsa and goads her into killing him - which she does contemplate, but ultimately can't do - and he takes her tear afterwards. He then takes the hat for himself, wanting to use it to collect enough magic to end his dagger's thrall over him, but the apprentice (still in mouse form) soon bites his hand and causes him to drop said dagger, which Anna then picks up and uses to force him to hand over the hatbox and send her back to Arendelle. He begrudgingly obliges, and she quickly reunites with Kristoff. ("The Apprentice")
The Apprentice comes to Ingrid with a solution. ("Smash the Mirror")
Ingrid arrives at the Apprentice's cottage and demands to make a deal with the Sorcerer. The Apprentice warns her that the Sorcerer does not make petty deals with those who embrace the darkness, but Ingrid says that she has the Sorcerer's Hat. The Apprentice warns that she has no idea what forces she is dealing with and draws his sword. He demands to know where it is, but Ingrid assures him that it is hidden far away. If the Sorcerer doesn't give her what she wants then the Sorcerer will never see his hat again. The Apprentice asks what she wants, and Ingrid says that she wants happiness: the kind she had with her sisters as a child. She explains that she wants two new sisters born of magic like her: Elsa and a third. The Apprentice warns that it will take time to find a perfect match, and Ingrid says that she will wait as long as it takes. After Ingrid froze Arendelle, she recovers the Sorcerer's Hat and the Apprentice arrives. He reminds her of her deal with the Sorcerer, and says that happy endings can take a long time but they do happen. The Sorcerer has found a third sister and she will be a perfect match... but she hasn't been born yet. The Apprentice warns that if Ingrid delivers the hat then she will never have her third sister or be reunited with Elsa. He conjures a door to a new land where her happy ending await, and offers to open it if she gives him the Hat. Ingrid wonders why the Sorcerer is making a deal with her now, and the Apprentice says that sometimes people can surprise others. She hands over the Hat and the Apprentice gives her a scroll and says that it will lead her to her third sister when the time comes. Ingrid steps through the door. ("Smash the Mirror")
The Apprentice banishes Maleficent's child to our world. ("Best Laid Plans")
Snow White and Prince Charming race to find a unicorn so that its magic horn will give them a vision of their unborn child's future; Charming sees a future where their baby is safe and happy, but Snow sees a future where their daughter is a villain, and she knows that something must be done to change it. They hear from a peddler - actually the Author - who they give some brandy to that Maleficent has taken dragon form in a cave and laid an egg, and he advises them to go into the Infinite Forest and seek out an old hermit who might be able to help them with their problem. The royal couple find the Sorcerer's Apprentice, and he explains how everyone is born a blank slate with the potential for both good and darkness; if they want their baby's potential for darkness to be eradicated, they must find another blank slate for that potential to be siphoned off into. As such, they head to Maleficent's cave and steal her egg from her, promising to bring it back once they're done with it. They take the egg to the Apprentice and he performs the spell, but this also involves sending the egg to another world. Snow and Charming are appalled, especially once the egg starts to hatch and they see that a baby is inside. Cruella De Vil and Ursula try their best to stop the so-called heroes, but they merely end up being sucked into the portal as well, banished to an unknown realm. Snow and Charming are left to deal with the gravity of what they have just caused, and the Apprentice later approaches the Author and wonders how he could make him do that to a poor child. The Author says that it makes for a better story, and so the Apprentice traps him in a page of his book for having forsaken his holy duty. ("Best Laid Plans")
The Apprentice has queries. ("Lily")
The Apprentice rushes into the Sorcerer's lair in order to warn him of the fact that the Author forsook his holy duty by using his magic to manipulate events majorly, having made it so that Maleficent's child had the savior's darkness siphoned off into her before being banished to a land without magic. The Apprentice warns the Sorcerer not to worry, however, for he trapped the Author inside the book - from inside it, he may only be able to record events; manipulation is impossible. He is curious as to what will become of Snow's and Maleficent's respective daughters, and the disembodied Sorcerer says that their fates shall remain entwined, just as they always were, telling his Apprentice to just make sure that the Author is never allowed to manipulate fate ever again. ("Lily")
After the Curse
I can see you have a lot of questions; fortunately I have a lot of answers.
Lily is told of her heritage. ("Lily")
Lily - the now-teenage daughter of Maleficent growing up helplessly in a land without magic - is sitting on a bus after having just departed from Emma, the savior. The Apprentice is seen in the seat next to her, asking if she ever noticed how her mother's moon-shaped necklace complements the star-shaped birth mark on her wrist, and Lily grows confused. The Apprentice reveals that he knows exactly who she is and where she's from, while she has no idea, and he's not supposed to be telling her this, but he feels that she has a right to know and understand her background. He starts by telling her about her mother, going on to explain about Storybrooke (the town which the Enchanted Forest residents were brought by the Queen's curse), the concept of a savior, the fact that Snow and Charming had their daughter's darkness transferred into her as a mere dragon's egg, and so on. ("Lily")
After the Second Curse
The Apprentice is absorbed into the sorcerer's hat. ("The Apprentice")
After being enchanted by Mr. Gold, the walking broom reaches its destination as it approaches a small house. Hook wonders who its leading them to, so Rumple explains that its someone who wronged him long ago and must now pay the price. The broom reaches the door and them loses its magic, resting on the wall as a normal broom. Rumple knocks on the door...and the Apprentice answers, he looks terrified. "Hello, old friend" Rumple smiles menacingly before telling Hook to show their host to a seat. Hook grabs the old man and takes him further into the house, placing him down on a chair. Rumple follows, carrying the hat box, and he places it down on the floor before the scared old man. Rumple takes out his dagger and waves it over the box, activating it so the hat emerges. "You have it?" the old man asks, shocked. Rumple says he shouldn't have doubted him, but the old man points out every Dark One tries and every one fails, "It might be time to update the motto" Rumple tells him. The apprentice tells Rumple that although he has the hat, he'll never collect enough power to do what he wants. "Oh I will" he responds confidently, "But alas, you won't be there to see it" he says before turning the hat on its side, exposing the apprentice to the underneath. A powerful vortex opens and sucks the old man inside, much to the horror of Hook, "Where the hell did he go?" he asks as Rumple picks up the hat. "Exactly where I need him" Rumple replies, looking at the starry hat. ("The Apprentice")
The Apprentice is set free. ("Operation Mongoose, Part 1")
With the Author now having the enchanted ink he needs in order to rewrite everyone's stories, Emma and the others head to the Sorcerer's mansion in order to search through all the blank books to see if any are being filled out. None are, and they almost declare their plunder pointless; that is, until August shows up and advises them to find the man who turned Isaac into the Author in the first place - the Apprentice. He shows them an illustration of the old wizard and Hook, having been blackmailed by Rumple to trap him in the hat, is able to recognize him, leading the group to his house. Mother Superior is implored to help free him, and she says that she might be able to succeed without the Dark One's dagger if she uses something which belonged to the Apprentice. Hook hands her the magic broom leaning up against the wall and Blue works her magic over both that and the hat box. Eventually, the Apprentice is set free in a bright flash of yellow light and tells everyone that they have to retrieve the page and re-trap the Author... but it's too late. Isaac finishes his writing as Emma, Regina and the Apprentice rush to stop him and everyone is transported to an upside-down world where the tables are turned on heroes and villains alike. ("Operation Mongoose, Part 1")
Emma saves the Apprentice from being consumed by the darkness. ("Operation Mongoose, Part 2")
In this backwards world, Henry Mills is able to fix everything by becoming the new Author and using Regina's sacrificial blood to write everything back to the way it was before Isaac's meddling. The Apprentice wake sup in the middle of the street, and Isaac is arrested by the Charmings. Henry contemplates using his new powers to bring back Baelfire, his father, but the Apprentice explains that even an Author isn't capable of bringing back the dead. He knows the temptation to change fate is strong, but Henry ends up snapping his quill, declaring that no one should have that kind of power. This leads the Apprentice to conclude that, this time, they've found the right person for the job. Soon, Rumplestiltskin collapses due to all the darkness swarming his heart, and Belle rushes to get the Apprentice's help. He removes all the darkness using the Sorcerer's hat, but the hat can't contain it all and the darkness escapes, attacking the old wizard. Emma is able to repel it with her light magic but the Apprentice is fatally weakened. He is made comfortable and explains to Emma that, eons ago, the Sorcerer battled the darkness and tethered it to a human soul that could be controlled by a dagger - the Dark One. He tasks the savior with finding him, for he is far away, and reveals his name to be Merlin. He proceeds to close his eyes, and Emma goes on to become the new Dark One. ("Operation Mongoose, Part 2")
I am too weak now, but this... will help. It is a gift from the Sorcerer, from Merlin, on the day I became his apprentice.
Before dying, the Apprentice passes on his wand. ("The Dark Swan")
Hook, Regina, Robin and the Charmings file into the back room of Mr. Gold Pawnbroker & Antiquities Dealer, where Mother Superior is tending to a very weak Sorcerer's Apprentice. Hook reveals to the old wizard that "that monstrosity" took Emma, and he needs to know where it went. The Apprentice reveals in turn that she is now where all darkness is born: in their realm, and Hook demands that he take them there. The Apprentice says that he's too weak now, but is able to make his magic wand appear in his hand, telling them that it will help. It was a gift from the Sorcerer - from Merlin - on the day he became his apprentice; inside it is all the light magic. Mary Margaret asks if it can take them to her daughter, but the Apprentice explains that, in order to cross realms, the wand must be wielded as it was forged: with both sides of the coin; the light and the dark. As he utters this, his eyes close and his body goes slack. The wand drops to the floor as he finally dies, and Mother Superior looks sorry for her patient. ("The Dark Swan")
The Apprentice delivers a warning. ("The Brothers Jones")
After dying, the Apprentice's soul traveled to the Underworld due to him having unfinished business regarding Henry, who ends up going there himself alongside his family on a mission to save Captain Hook. Henry learns from Cruella De Vil that the Author's magic quill is down there, for it was a living breathing entity and when he snapped it it epitomized unfinished business. The two of them try to find it together so that he can resurrect her and make his mother Emma no longer a murderer, but during the search he is approached by the Apprentice. He tells Henry not to resurrect Cruella De Vil, apologizing for lying to him before about not being able to bring people back from the dead because he didn't want to tempt him. Ultimately though, he tells the young man that the magic quill is in Merlin's mansion, explaining that he now has a choice to make... but the Apprentice shan't be able to move on unless Henry makes the right one. Luckily, he does. ("The Brothers Jones")
Gallery of photographic stills released to promote the character.